热镀锌过程挡板对镀层均匀性影响的模拟研究

Computational studies on coating uniformity influenced by baffle in hot dip galvanizing process

为解决热镀锌过程中常出现的边部过镀锌缺陷,利用数值模拟方法对热镀锌气刀射流喷吹过程进行仿真研究,分析了挡板厚度对带钢边部压力场的影响;并借助镀层厚度计算模型,计算挡板厚度和边部角度对镀层厚度的作用关系;同时通过不同拉钢速度、气刀狭缝总压等工况,对挡板的厚度及边部角度进行优化.结果表明:随挡板厚度减小,带钢边部作用力增大并逐渐接近中心处;带钢边部镀层厚度随挡板厚度的减小而变薄,随挡板边部角度的增加而先减小后增大;挡板厚度2 mm、边部角度90°时,能有效提高带钢横向作用力和镀层分布的均匀性.

Numerical simulation of the gas-jet wiping in hot dip galvanizing process was conducted,aiming to reduce the possible of edge over coating（ EOC）. The effects of baffle thickness and edge angle on pressure fields of strip edge were studied. By using the analytic model of film thickness,the correlation betweent the coating thickness and baffle thickness and edge angle was revealed. Considering different conditions of steel moving speed and total gas knife pressure,the baffle thickness and edge angle were optimized. The results show that the coating thickness of strip edge increases with the decrease of baffle thickness. In addition,with the increase of baffle edge angle,the coating thickness decreases firstly and then increases. When the baffle thickness is 2 mm and the angle is 90°,uniformity distribution of the pressure and coating on the strip is achieved.